The need to decrease energy usage and subsequent emissions from the building sector has been at the forefront of U.S. green movement. Not only has energy reduction been viewed as a step for improving the environment, it has financial benefits for companies and homeowners.
To address this, researchers at the Massachusetts Institute of Technology’s (MIT) Concrete Sustainability Hub conducted a life-cycle assessment (LCA) study to evaluate and improve the environmental impact and study how the “dual use” aspect of concrete – its ability to offer a durable structure while providing thermal mass benefits for energy loads – affects the environmental footprint of the structure.
"Methods, Impacts, and Opportunities in the Concrete Building Life Cycle" provides a comprehensive analysis that advances three key areas relevant to the buildings LCA field: methodology, benchmarking, and impact-reduction opportunities. The study is a major development for construction-related life-cycle assessment because it thoroughly examines all phases of the complete life cycle of a building – from acquisition of materials to construction, the use of the building, and finally demolition and end of life.
“Most environmental assessments do not move beyond the construction phase and only provide a partial picture of the full impact a particular material can have on a building. This is short-sighted,” David Shepherd, director of sustainable development for the Portland Cement Association (PCA) said. “The heating, cooling, and general operations of buildings and homes in the United States accounts for approximately 70 percent of national energy consumption each year and an accurate LCA needs to include the operational phase.”
Concrete, essential for the construction of buildings and homes, has largely been chosen as a building material for its structural properties rather than its energy-saving properties. Although sustainable builders have known the thermal mass attributes of concrete significantly reduce heating and cooling needs, the energy consumption required to produce its key ingredient, cement, has raised questions about its environmental viability.
In its environmental assessment, MIT researchers found concrete homes produce lower greenhouse gas emissions than current best practice code – compliant wood-frame residences throughout a 60-year service life.
Concrete homes did have a higher embodied global warming potential (GWP) associated with the pre-use phase of LCA when raw materials are harvested and turned into construction materials, transported to the site, and assembled into the finished home. However, this phase accounts for only about 2 to 12%of the overall global warming potential for the life of the home. For the 60-year period of the study, houses constructed with insulated concrete forms have 5 to 8 percent lower GWP than current code compliant light frame wood houses, based on greater thermal mass and higher R-values. Researchers found similar results when evaluating multifamily residences.
Commercial office buildings built with a concrete structural frame produce slightly less greenhouse gas emissions over a 60-year service life than commercial structures built with steel frames, based on the results of the comprehensive MIT assessment.
MIT researchers then evaluated strategies to lower a concrete building’s carbon footprint and overall environmental impact. A major advancement was the incorporation of a cost-impact analysis to determine whether or not a given environmental reduction strategy made economic sense. Among the strategies evaluated, the two that reduced embodied emissions – increased fly ash and reducing the thickness of concrete walls from a 6-inch to a 4-inch concrete core – were found to be both economical and effective ways to reduce emissions. BD+C
Related Stories
Multifamily Housing | Apr 21, 2023
Arlington County, Va., eliminates single-family-only zoning
Arlington County, a Washington, D.C., community that took shape in the 1950s, when single-family homes were the rule in suburbia, recently became one of the first locations on the East Coast to eliminate single-family-only zoning.
Architects | Apr 21, 2023
Architecture billings improve slightly in March
Architecture firms reported a modest increase in March billings. This positive news was tempered by a slight decrease in new design contracts according to a new report released today from The American Institute of Architects (AIA). March was the first time since last September in which billings improved.
Green | Apr 21, 2023
Top 10 green building projects for 2023
The Harvard University Science and Engineering Complex in Boston and the Westwood Hills Nature Center in St. Louis are among the AIA COTE Top Ten Awards honorees for 2023.
Multifamily Housing | Apr 19, 2023
Austin’s historic Rainey Street welcomes a new neighbor: a 48-story mixed-used residential tower
Austin’s historic Rainey Street is welcoming a new neighbor. The Paseo, a 48-story mixed-used residential tower, will bring 557 apartments and two levels of retail to the popular Austin entertainment district, known for houses that have been converted into bungalow bars and restaurants.
Design Innovation Report | Apr 19, 2023
Reinforced concrete walls and fins stiffen and shade the National Bank of Kuwait skyscraper
When the National Bank of Kuwait first conceived its new headquarters more than a decade ago, it wanted to make a statement about passive design with a soaring tower that could withstand the extreme heat of Kuwait City, the country’s desert capital.
Design Innovation Report | Apr 19, 2023
HDR uses artificial intelligence tools to help design a vital health clinic in India
Architects from HDR worked pro bono with iKure, a technology-centric healthcare provider, to build a healthcare clinic in rural India.
Design Innovation Report | Apr 19, 2023
Meet The Hithe: A demountable building for transient startups
The Hithe, near London, is designed to be demountable and reusable. The 2,153-sf building provides 12 units of business incubator workspace for startups.
Metals | Apr 19, 2023
Sherwin-Williams Coil Coatings releases new color forecast for architectural metal coatings
The Coil Coatings division of Sherwin-Williams has released its latest color forecast, FUSE, for architectural metal coatings. The report aims to inspire architects, product manufacturers and original equipment manufacturers (OEMs) in the coil and extrusion market over the next 3-5 years and beyond.
Airports | Apr 18, 2023
India's mammoth new airport terminal takes ‘back to nature’ seriously
On January 15, 2023, Phase 1 of the Kempegowda International Airport’s Terminal 2, in Bengaluru, India, began domestic operations. The 2.75 million-sf building, designed by Skidmore, Owings & Merrill (SOM), is projected to process 25 million passengers annually, while providing its travelers with a healthier environment, thanks to extensive indoor-outdoor landscaping that offers serenity to what is normally a frenzied experience.
Resiliency | Apr 18, 2023
AI-simulated hurricanes could aid in designing more resilient buildings
Researchers at the National Institute of Standards and Technology (NIST) have devised a new method of digitally simulating hurricanes in an effort to create more resilient buildings. A recent study asserts that the simulations can accurately represent the trajectory and wind speeds of a collection of actual storms.